854
FNCA52 TJSJ 181930
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST TUE AUG 18 2026
DISCUSSION
CRITICAL FUEL CONDITIONS CONTINUE ACROSS THE ISLANDS, WITH
EXTREME DROUGHT AFFECTING THE SOUTHERN COASTAL PLAINS AND EASTERN
PUERTO RICO. GENERALLY DRY CONDITIONS HAVE PREVAILED TODAY, WITH
LOW RELATIVE HUMIDITY, STRESSED VEGETATION, AND DRY FUELS
CONTINUING TO SUPPORT AN ELEVATED FIRE DANGER. THE GREATEST
CONCERN REMAINS ACROSS SOUTHERN AND SOUTHWESTERN PUERTO RICO,
WHERE FUELS ARE EXCEPTIONALLY DRY AND RECENT FIRE ACTIVITY HAS
BEEN FREQUENT. A GRADUAL INCREASE IN MOISTURE IS EXPECTED THIS
AFTERNOON TO EVENING, AS A TROPICAL WAVE, AND ITS MOISTURE FIELD,
APPROACHES THE ISLANDS. ALTHOUGH SOME RELIEF IS POSSIBLE,
UNCERTAINTY PERSISTS REGARDING THE COVERAGE OF RAINFALL. A FIRE
DANGER STATEMENT CONTINUES THROUGH 5 PM AST FOR THE SOUTHERN AND
SOUTHWESTERN PLAINS OF PUERTO RICO. RESIDENTS AND VISITORS ARE
STRONGLY URGED TO AVOID OUTDOOR BURNING, AS CONDITIONS WILL
EASILY SUPPORT WILDFIRE IGNITION AND RAPID SPREAD.
PRZ014-190800-
SOUTHEAST COASTAL PLAINS-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS TSTMS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 30 20 0
TEMP (24H TREND) 75 (-2) 91 (-1) 75 92
RH % (24H TREND) 94 (+7) 58 (+2) 94 50
WIND 20FT/EARLY(MPH) E 16 E 12 E 11 E 16
WIND 20FT/LATE(MPH) NE 10 SE 13 E 13 E 16
MIXING HGT(FT-AGL/MSL) 4650 4740
TRANSPORT WND (MPH) SE 14 E 17
VENT RATE (KT-FT) 55800 71100
DISPERSION 5 5
DSI 3 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ015-190800-
SOUTHERN HILLS-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS TSTMS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 40 20 10
TEMP (24H TREND) 71 (-3) 89 (+1) 71 90
RH % (24H TREND) 99 (+7) 64 (+4) 99 56
WIND 20FT/EARLY(MPH) E 12 E 11 E 10 E 13
WIND 20FT/LATE(MPH) NE 10 SE 11 E 13 E 13
MIXING HGT(FT-AGL/MSL) 5470 5600
TRANSPORT WND (MPH) SE 13 E 17
VENT RATE (KT-FT) 60170 84000
DISPERSION 5 5
DSI 3 6 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ016-190800-
NORTH COASTAL PLAINS-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 10 40 40 30
TEMP (24H TREND) 74 (-3) 91 (+1) 74 92
RH % (24H TREND) 100 (+7) 62 (-3) 100 57
WIND 20FT/EARLY(MPH) E 13 E 12 SE 12 E 13
WIND 20FT/LATE(MPH) E 12 E 17 SE 12 E 21
MIXING HGT(FT-AGL/MSL) 5000 4930
TRANSPORT WND (MPH) E 13 E 18
VENT RATE (KT-FT) 55000 78880
DISPERSION 5 5
DSI 5 5 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ017-190800-
NORTHERN HILLS-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY PCLDY MCLEAR
PRECIP TYPE NONE TSTMS SHOWERS TSTMS
CHANCE PRECIP (%) 0 60 30 30
TEMP (24H TREND) 72 (-2) 90 (+1) 71 91
RH % (24H TREND) 100 (+3) 67 (+4) 100 58
WIND 20FT/EARLY(MPH) E 12 E 10 SE 10 E 12
WIND 20FT/LATE(MPH) E 11 E 13 SE 6 E 18
MIXING HGT(FT-AGL/MSL) 5930 6690
TRANSPORT WND (MPH) SE 9 E 14
VENT RATE (KT-FT) 47440 80280
DISPERSION 5 5
DSI 3 5 3 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ018-190800-
WEST COAST-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY MCLEAR PCLDY
PRECIP TYPE NONE TSTMS SHOWERS TSTMS
CHANCE PRECIP (%) 0 50 30 30
TEMP (24H TREND) 73 (-1) 94 (+2) 74 93
RH % (24H TREND) 99 (+5) 62 (+1) 100 58
WIND 20FT/EARLY(MPH) E 14 SE 12 E 10 E 14
WIND 20FT/LATE(MPH) E 13 SE 13 E 11 E 14
MIXING HGT(FT-AGL/MSL) 4290 5120
TRANSPORT WND (MPH) SE 10 E 13
VENT RATE (KT-FT) 38610 56320
DISPERSION 5 5
DSI 3 5 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ019-190800-
EASTERN INTERIOR-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 30 40 40 20
TEMP (24H TREND) 73 (-3) 90 (+1) 73 91
RH % (24H TREND) 100 (+7) 63 (+2) 100 57
WIND 20FT/EARLY(MPH) E 11 SE 11 SE 11 E 16
WIND 20FT/LATE(MPH) E 11 SE 12 E 14 E 13
MIXING HGT(FT-AGL/MSL) 6270 5890
TRANSPORT WND (MPH) SE 13 E 17
VENT RATE (KT-FT) 68970 88350
DISPERSION 5 5
DSI 3 6 4 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ022-190800-
LUQUILLO MOUNTAIN RANGE-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY MCLDY PCLDY PCLDY
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 60 70 60 30
TEMP (24H TREND) 70 (-3) 86 (+3) 71 87
RH % (24H TREND) 100 (+4) 68 (-3) 100 64
WIND 20FT/EARLY(MPH) E 10 SE 10 SE 10 E 12
WIND 20FT/LATE(MPH) E 9 SE 11 E 12 E 12
MIXING HGT(FT-AGL/MSL) 4400 4460
TRANSPORT WND (MPH) SE 13 E 17
VENT RATE (KT-FT) 48400 66900
DISPERSION 5 5
DSI 5 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ023-190800-
CENTRAL MOUNTAIN RANGE-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY MCLEAR MCLEAR
PRECIP TYPE NONE TSTMS SHOWERS TSTMS
CHANCE PRECIP (%) 0 60 20 30
TEMP (24H TREND) 68 (-3) 87 (+2) 69 89
RH % (24H TREND) 100 (+3) 70 (+4) 100 61
WIND 20FT/EARLY(MPH) E 10 SE 8 SE 6 E 10
WIND 20FT/LATE(MPH) E 10 SE 10 E 5 E 10
MIXING HGT(FT-AGL/MSL) 6870 8150
TRANSPORT WND (MPH) SE 10 E 10
VENT RATE (KT-FT) 61830 73350
DISPERSION 5 5
DSI 2 5 2 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ024-190800-
CAYEY MOUNTAIN RANGE-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 50 40 10
TEMP (24H TREND) 71 (-2) 85 (0) 72 86
RH % (24H TREND) 100 (+3) 70 (+5) 100 64
WIND 20FT/EARLY(MPH) E 10 SE 9 E 9 E 11
WIND 20FT/LATE(MPH) E 8 SE 10 E 11 E 12
MIXING HGT(FT-AGL/MSL) 5120 4840
TRANSPORT WND (MPH) SE 13 E 17
VENT RATE (KT-FT) 56320 72600
DISPERSION 5 5
DSI 3 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ025-190800-
VIEQUES-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY MCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 70 70 60 10
TEMP (24H TREND) 78 (-2) 91 (+2) 80 91
RH % (24H TREND) 89 (+8) 57 (-4) 87 55
WIND 20FT/EARLY(MPH) E 14 SE 14 E 13 E 18
WIND 20FT/LATE(MPH) E 14 SE 12 E 18 E 16
MIXING HGT(FT-AGL/MSL) 2860 3750
TRANSPORT WND (MPH) SE 15 E 20
VENT RATE (KT-FT) 37180 63750
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ026-190800-
CULEBRA-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY MCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 70 70 60 10
TEMP (24H TREND) 78 (-3) 91 (+2) 79 91
RH % (24H TREND) 94 (+10) 60 (-7) 92 58
WIND 20FT/EARLY(MPH) E 14 SE 14 E 14 E 18
WIND 20FT/LATE(MPH) E 14 SE 12 E 19 E 16
MIXING HGT(FT-AGL/MSL) 2770 3590
TRANSPORT WND (MPH) SE 15 SE 20
VENT RATE (KT-FT) 36010 61030
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
PRZ027-190800-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLEAR PCLDY MCLEAR MCLEAR
PRECIP TYPE SHOWERS TSTMS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 40 10 10
TEMP (24H TREND) 75 (-1) 93 (+1) 75 94
RH % (24H TREND) 94 (+8) 58 (+1) 93 53
WIND 20FT/EARLY(MPH) E 16 E 17 E 14 E 20
WIND 20FT/LATE(MPH) E 11 SE 18 E 16 SE 20
MIXING HGT(FT-AGL/MSL) 4650 5050
TRANSPORT WND (MPH) SE 17 E 21
VENT RATE (KT-FT) 69750 90900
DISPERSION 5 5
DSI 3 6 5 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ001-190800-
SAINT THOMAS AND SAINT JOHN-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER PCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 70 70 50 10
TEMP (24H TREND) 77 (-3) 89 (+2) 78 89
RH % (24H TREND) 93 (+9) 61 (-6) 91 58
WIND 20FT/EARLY(MPH) E 13 SE 14 E 17 E 18
WIND 20FT/LATE(MPH) E 14 SE 12 E 19 E 17
MIXING HGT(FT-AGL/MSL) 2900 3550
TRANSPORT WND (MPH) SE 15 E 21
VENT RATE (KT-FT) 37700 63900
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
VIZ002-190800-
ST CROIX-
330 PM AST TUE AUG 18 2026
TONIGHT WED WED NIGHT THU
CLOUD COVER MCLDY PCLDY PCLDY MCLEAR
PRECIP TYPE TSTMS TSTMS TSTMS SHOWERS
CHANCE PRECIP (%) 60 50 40 10
TEMP (24H TREND) 78 (-2) 90 (+2) 78 90
RH % (24H TREND) 94 (+7) 62 (-7) 93 59
WIND 20FT/EARLY(MPH) E 13 SE 12 E 17 E 18
WIND 20FT/LATE(MPH) E 13 SE 12 E 18 E 17
MIXING HGT(FT-AGL/MSL) 4580 4440
TRANSPORT WND (MPH) SE 15 E 22
VENT RATE (KT-FT) 59540 84360
DISPERSION 5 5
DSI 6 6 6 6
RH RECOVERY EXCELLENT EXCELLENT
REMARKS...NONE.
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